cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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delay.h (1668B)

      1/*
      2 * include/asm-xtensa/delay.h
      3 *
      4 * This file is subject to the terms and conditions of the GNU General Public
      5 * License.  See the file "COPYING" in the main directory of this archive
      6 * for more details.
      7 *
      8 * Copyright (C) 2001 - 2005 Tensilica Inc.
      9 *
     10 */
     11
     12#ifndef _XTENSA_DELAY_H
     13#define _XTENSA_DELAY_H
     14
     15#include <asm/timex.h>
     16#include <asm/param.h>
     17
     18extern unsigned long loops_per_jiffy;
     19
     20static inline void __delay(unsigned long loops)
     21{
     22	if (__builtin_constant_p(loops) && loops < 2)
     23		__asm__ __volatile__ ("nop");
     24	else if (loops >= 2)
     25		/* 2 cycles per loop. */
     26		__asm__ __volatile__ ("1: addi %0, %0, -2; bgeui %0, 2, 1b"
     27				: "+r" (loops));
     28}
     29
     30/* Undefined function to get compile-time error */
     31void __bad_udelay(void);
     32void __bad_ndelay(void);
     33
     34#define __MAX_UDELAY 30000
     35#define __MAX_NDELAY 30000
     36
     37static inline void __udelay(unsigned long usecs)
     38{
     39	unsigned long start = get_ccount();
     40	unsigned long cycles = (usecs * (ccount_freq >> 15)) >> 5;
     41
     42	/* Note: all variables are unsigned (can wrap around)! */
     43	while (((unsigned long)get_ccount()) - start < cycles)
     44		cpu_relax();
     45}
     46
     47static inline void udelay(unsigned long usec)
     48{
     49	if (__builtin_constant_p(usec) && usec >= __MAX_UDELAY)
     50		__bad_udelay();
     51	else
     52		__udelay(usec);
     53}
     54
     55static inline void __ndelay(unsigned long nsec)
     56{
     57	/*
     58	 * Inner shift makes sure multiplication doesn't overflow
     59	 * for legitimate nsec values
     60	 */
     61	unsigned long cycles = (nsec * (ccount_freq >> 15)) >> 15;
     62	__delay(cycles);
     63}
     64
     65#define ndelay(n) ndelay(n)
     66
     67static inline void ndelay(unsigned long nsec)
     68{
     69	if (__builtin_constant_p(nsec) && nsec >= __MAX_NDELAY)
     70		__bad_ndelay();
     71	else
     72		__ndelay(nsec);
     73}
     74
     75#endif